

<template>
  <div class="banner">
  <div class="item">
    <img :src="dataList[currentIndex]">
  </div>
  <div class="page" v-if="this.dataList.length > 1">
    <ul>
      <li @click="gotoPage(prevIndex)">&lt;</li>
      <li v-for="(item,index) in dataList" @click="gotoPage(index)" :class="{'current':currentIndex == index}" :key="index">  {{index+1}}</li>
      <li @click="gotoPage(nextIndex)">&gt;</li>
    </ul>
  </div>
</div>
</template>

<script>
// Sun Dec 5 14:17:45 CST 2021
// slide 轮播图 current 现在的
// width:785px   height:294px
export default {
  name: '',
  data () {
    return {
      dataList:["https://i1.mifile.cn/a4/xmad_15535933141925_ulkYv.jpg","https://i1.mifile.cn/a4/xmad_15532384207972_iJXSx.jpg","https://i1.mifile.cn/a4/xmad_15517939170939_oiXCK.jpg"],
      currentIndex:0,
      timer: null
    }
  },
  methods: {
    gotoPage(index) {
        this.currentIndex = index;
         }
  }
  ,computed:{
      //上一张
    prevIndex(){
        if(this.currentIndex == 0) {
            return this.dataList.length - 1;
        }else{
            return this.currentIndex - 1;
        }
    },
    //下一张
    nextIndex(){
        if(this.currentIndex == this.dataList.length - 1) {
            return 0;
        }else {
            return this.currentIndex + 1;
        }
  },
  mounted() {
      //定时器
        this.timer = setInterval(() => {
            console.log("timer已经执行")
            this.gotoPage(this.nextIndex)
    }, 1000)
  },
}
}
</script>

<style>
    * {
        margin: 0;
        padding: 0;
    }
    ul li {
        list-style: none;
        float: left;
        width: 30px;
        height: 40px;
        line-height: 40px;
        text-align: center;
        cursor: pointer;
        color: rgba(255,255,255,.8);
        font-size: 14px;
    }
    .banner {
        max-width: 1200px;
        margin: 0 auto;
        position: relative;
        margin-top: 60px;
    }
    .banner img {
        width: 100%;
        display: block;
    }
    .banner .page {
        background: rgba(0,0,0,.5);
        position: absolute;
        right: 0;
        bottom: 0;
        width: 100%;
    }
    .banner .page ul {
        float: right;
    }
    .current {
        color: #ff6700;
    }
</style>
